Initial fork commit.

Signed-off-by: Pavel Kirilin <s3riussan@gmail.com>

core/outbound_check.go

@@ -0,0 +1,40 @@
+package core
+
+import (
+	"context"
+	"time"
+
+	urltest "github.com/sagernet/sing-box/common/urltest"
+)
+
+const checkTimeout = 15 * time.Second
+
+type CheckOutboundResult struct {
+	OK    bool
+	Delay uint16
+	Error string
+}
+
+func CheckOutbound(ctx context.Context, tag string, link string) (result CheckOutboundResult) {
+	if outbound_manager == nil {
+		result.Error = "core not running"
+		return result
+	}
+	ob, ok := outbound_manager.Outbound(tag)
+	if !ok {
+		result.Error = "outbound not found"
+		return result
+	}
+
+	ctx, cancel := context.WithTimeout(ctx, checkTimeout)
+	defer cancel()
+
+	delay, err := urltest.URLTest(ctx, link, ob)
+	if err != nil {
+		result.Error = err.Error()
+		return result
+	}
+	result.OK = true
+	result.Delay = delay
+	return result
+}